1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
UNO [17]
2 years ago
5

Simplify each expression below.

Mathematics
1 answer:
Natalija [7]2 years ago
6 0

Answer:

C) 45-38

Step-by-step explanation:

The reason why this is your answer is because if we subtract, the answer is less than 12.

Thanks!

You might be interested in
Four buses carrying 146 high school students arrive to Montreal. The buses carry, respectively, 32, 44, 28, and 42 students. One
Naily [24]

Answer:

The expected value of X is E(X)=\frac{2754}{73} \approx 37.73 and the variance of X is Var(X)=\frac{226192}{5329} \approx 42.45

The expected value of Y is E(Y)=\frac{73}{2} \approx 36.5 and the  variance of Y is Var(Y)=\frac{179}{4} \approx 44.75

Step-by-step explanation:

(a) Let X be a discrete random variable with set of possible values D and  probability mass function p(x). The expected value, denoted by E(X) or \mu_x, is

E(X)=\sum_{x\in D} x\cdot p(x)

The probability mass function p_{X}(x) of X is given by

p_{X}(28)=\frac{28}{146} \\\\p_{X}(32)=\frac{32}{146} \\\\p_{X}(42)=\frac{42}{146} \\\\p_{X}(44)=\frac{44}{146}

Since the bus driver is equally likely to drive any of the 4 buses, the probability mass function p_{Y}(x) of Y is given by

p_{Y}(28)=p_{Y}(32)=p_{Y}(42)=p_{Y}(44)=\frac{1}{4}

The expected value of X is

E(X)=\sum_{x\in [28,32,42,44]} x\cdot p_{X}(x)

E(X)=28\cdot \frac{28}{146}+32\cdot \frac{32}{146} +42\cdot \frac{42}{146} +44 \cdot \frac{44}{146}\\\\E(X)=\frac{392}{73}+\frac{512}{73}+\frac{882}{73}+\frac{968}{73}\\\\E(X)=\frac{2754}{73} \approx 37.73

The expected value of Y is

E(Y)=\sum_{x\in [28,32,42,44]} x\cdot p_{Y}(x)

E(Y)=28\cdot \frac{1}{4}+32\cdot \frac{1}{4} +42\cdot \frac{1}{4} +44 \cdot \frac{1}{4}\\\\E(Y)=146\cdot \frac{1}{4}\\\\E(Y)=\frac{73}{2} \approx 36.5

(b) Let X have probability mass function p(x) and expected value E(X). Then the variance of X, denoted by V(X), is

V(X)=\sum_{x\in D} (x-\mu)^2\cdot p(x)=E(X^2)-[E(X)]^2

The variance of X is

E(X^2)=\sum_{x\in [28,32,42,44]} x^2\cdot p_{X}(x)

E(X^2)=28^2\cdot \frac{28}{146}+32^2\cdot \frac{32}{146} +42^2\cdot \frac{42}{146} +44^2 \cdot \frac{44}{146}\\\\E(X^2)=\frac{10976}{73}+\frac{16384}{73}+\frac{37044}{73}+\frac{42592}{73}\\\\E(X^2)=\frac{106996}{73}

Var(X)=E(X^2)-(E(X))^2\\\\Var(X)=\frac{106996}{73}-(\frac{2754}{73})^2\\\\Var(X)=\frac{106996}{73}-\frac{7584516}{5329}\\\\Var(X)=\frac{7810708}{5329}-\frac{7584516}{5329}\\\\Var(X)=\frac{226192}{5329} \approx 42.45

The variance of Y is

E(Y^2)=\sum_{x\in [28,32,42,44]} x^2\cdot p_{Y}(x)

E(Y^2)=28^2\cdot \frac{1}{4}+32^2\cdot \frac{1}{4} +42^2\cdot \frac{1}{4} +44^2 \cdot \frac{1}{4}\\\\E(Y^2)=196+256+441+484\\\\E(Y^2)=1377

Var(Y)=E(Y^2)-(E(Y))^2\\\\Var(Y)=1377-(\frac{73}{2})^2\\\\Var(Y)=1377-\frac{5329}{4}\\\\Var(Y)=\frac{179}{4} \approx 44.75

8 0
3 years ago
Write the following in terms of sin θ only.<br> cot θ
sveta [45]
\bf cot(\theta)=\cfrac{cos(\theta)}{sin(\theta)}&#10;\\\\\\&#10;sin^2(\theta)+cos^2(\theta)=1\implies cos^2(\theta)=1-sin^2(\theta)&#10;\\\\\\&#10;cos(\theta)=\pm\sqrt{1-sin^2(\theta)}\\\\&#10;-----------------------------\\\\&#10;cot(\theta)=\cfrac{cos(\theta)}{sin(\theta)}\implies cot(\theta)=\cfrac{\pm\sqrt{1-sin^2(\theta)}}{sin(\theta)}
6 0
3 years ago
Someone pls help me!! thank you!!
romanna [79]

Final Answer is 4.5

= 4.5hours more time was used on games than on research.

6 0
3 years ago
Draw a double number line to solve the following rate problem.
IgorLugansk [536]
The ratio here is

  3/4 cup milk                                          6 cups milk
--------------------    Now equate this to    -----------------
 1 beaten egg                                                x

Solving this equation, (3/4)x = 6, and x = 8 (eggs)   (answer)


Check:  Note that 3/4    /    1    =   6  /   8
5 0
3 years ago
Read 2 more answers
If it takes 5 workers 4 hours to build a 10 foot wall, and the number of hours is directly proportional to the number of walls t
pychu [463]
4x10=40 10x10=100 ft/10 100/10=10 walls
4 0
3 years ago
Other questions:
  • What is the measure of angle 7?
    5·1 answer
  • Write the number in standard notation. 9.07 x 10−2
    14·2 answers
  • Calculate the exact lengths of segment e and segment f. Which is longer?
    7·1 answer
  • I need help in this question
    9·1 answer
  • Each number is a factor of the number <br> 2 3 6 9<br> which number could be the the number
    6·1 answer
  • What is the inverse of the function h(x)=5+x/4-2x
    5·1 answer
  • Eva tried to evaluate an expression step by step.
    13·1 answer
  • (2x^2+3x^3-16-8x) / (x-2)
    10·1 answer
  • Find the surface area and volume OF THIS QUESTION TOO (question 99)
    13·1 answer
  • Evaluate the expression:<br> -17-14=
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!